# STC SA622CH

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Duncan Aviation, United States
- Description: Replace two Pratt & Whitney model PT6A-112 engines with two Pratt & Whitney model PT6A-135/135A engines and Hartzell model HC-B3TN-3(C, K)/ T10178(B, K)-8R propellers.
- Status date: February 12, 1997
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A7CE](https://openairdocs.org/tcds/A7CE)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/ED575F1D992C3AF385256CC200569EE5.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA622CH

## ADs that name it (0)

None.

## Approved models (1)

- The Cessna Aircraft Company 425 ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))

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